"I want you to know that breast-feeding is normal," she said.
It's also a legally protected right in Virginia, where the legislature passed a 2015 law that says any woman has a right to breast-feed at any location where she has a legal right to be.
Now Peguero, and a lawyer, are pressing church leaders to issue a statement and reverse their policy.
"I feel like my rights as a mum have been violated," Peguero said.
Officials with the church did not immediately respond to requests for comment from the Post. Lawyer Rebecca Geller said today that she got a call from executive pastor Tony Trayers after repeated calls to Summit Church and was told that the church was not aware of the law and would look into it. There is no exemption for religious institutions under the law.
Peguero, a 42-year-old personal trainer and fitness and nutrition specialist, often posts live videos online with tips and advice about juggling life with two young children. She talks about getting through the day when a spouse is deployed, drawing on her own experience as the wife of a Marine serving overseas.
The self-described "hippie mama" said she looked forward to breast-feeding long before she had children.
"I knew it was the very best thing for my baby," she said. "I wanted to give them that gift for as long as I could and that's what I did."
She nursed her older daughter - now 4 years old - until she was eight-and-a-half months pregnant with Autumn. In all that time she never had a problem nursing in public, she said.
"I have breast-fed in a few different countries. I have breast-fed all over the place," she said. "No one has ever said anything to me."
Virginia was one of the last states to pass a law protecting a woman's right to breast-feed in public.
Prior to passage, women in Virginia had the right to nurse their babies on state-owned property, but restaurants and other privately owned businesses that were open to the public could prohibit it.
Under identical bills, mothers were permitted to breast-feed anywhere they are "lawfully present". The measures cleared the Republican-controlled House and Senate without opposition and were signed into law by Democratic Governor Terry McAuliffe.
Geller, who advocated for the 2015 law, said she has seen other breast-feeding flare ups since the law passed, but usually organisations are quick to reverse their policies when they learn about it.
She is "stunned" that the church has not followed suit, she said.
"Breast-feeding is hard enough for moms alone, much less when you have barriers," Geller said. "Why should she have to choose between feeding her child and being able to pray?"
Peguero said she has only attended the non-denominational church a half-dozen times, but she found it at a critical moment in her life.
She went for the first time in January on her birthday, hours after she broadcast a live video on Facebook asking for help her find her birth mother.
After the service, a friend introduced her to the pastor who prayed with her about her search. "It was beautiful," she said.
Soon afterward, she received a phone call from one of her birth mother's brothers, she said. She learned that her mother died in a car accident more than 20 years ago, but she is now in contact with her extended biological family, including 26 cousins.
She has returned to church since, often writing notes from the sermons in her leather-bound weekly planner so she can reflect on them later.
"This is a church that has brought me so much clarity," she said. "It's brought me back to my faith,."
Now, she no longer feels welcome.
"I can never go back there," she said.
